Analysis of Pendimethalin Residues in Fruit, Nuts, Vegetables, Grass, and Mint by Gas Chromatography

Abstract

Pendimethalin [N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine], in the formulation of Prowl (a commercial herbicide), was applied to various crops. Analysis of pendimethalin and its metabolite [4(1-ethylpropyl)amino-2-methyl-3,5-dinitrobenzyl alcohol] was accomplished by utilizing liquid-liquid partitioning, gel permeation chromatography (GPC) for nuts and mint, solid-phase extraction (SPE) cleanup, and gas chromatography (GC) with a nitrogen--phosphorus detector (NPD). Method validation recoveries for fruits, nuts, vegetables, grass, and mint are given for both compounds. Pendimethalin average recoveries ranged from 71% to 126% over two levels of fortification. Pendimethalin metabolite average recoveries ranged from 69% to 123% over two levels of fortification. The quantitation limit for all crops except mint was 0.050 ppm. The quantitation limit for mint and mint oil was 0.10 ppm. Residues greater than the limit of quantitation were found for pendimethalin in apple pomace, fresh and dry fig, grass screenings, mint oil, almond hulls, green onion, and tomato pomace (wet and dry). Residues greater than the limit of quantitation were found for pendimethalin metabolite in grass screenings, grass straw, and almond hulls. All other crop analyses for pendimethalin and its metabolite were below the limit of quantitation.

Simultaneous analysis of herbicides pendimethalin, oxyfluorfen, imazethapyr and quizalofop-p-ethyl by LC–MS/MS and safety evaluation of their harvest time residues in peanut (Arachis hypogaea L.)

“…Different chromatographic methods, such as liquid chromatography (LC) (Maldaner et al 2008;Sondhia, 2010;Shah et al 2011), capillary electrophoresis (Han et al 2008), gas chromatography (GC) (Engebretson et al 2001;Fenoll et al 2008;Hu et al 2010) and enzyme-linked immunoassay (Steinheimer and Scoggin, 1998;Zeng et al 2006) have been used till date for the determination of these herbicide residues in different matrices. In comparison with conventional techniques of GC and LC, LC hyphenated with tandem mass spectrometry (LC-MS/MS) is a prevailing technique in pesticide residues analysis, as the number of polar and non-GCamenable pesticides used in oilseeds is increasing.…”

Determination of herbicide residues in juice by matrix solid-phase dispersion and gas chromatography–mass spectrometry

“…Methods used to determine herbicide residues in fruits and vegetables are mainly based on liquid partitioning with organic solvents such as ethyl acetate, acetonitrile, and dichloromethane, usually followed by a solid-phase extraction cleanup step [1][2][3][4][5][6]. In the last years, new extraction procedures have been developed to overcome the drawbacks caused by using high amounts of glassware and toxic solvents in the classical liquid extraction methods.…”

“…The determination of herbicides in fruits and vegetables can be performed by gas chromatography with electroncapture detection (ECD) [11,13] or nitrogen-phosphorus detection (NPD) [6,12], when herbicide molecules have functional groups giving a selective and sensitive response with those detectors. Gas chromatography coupled with mass spectrometry has also been employed in the determination of herbicides due to its high selectivity when used in the selected ion monitoring (SIM) mode [2,4,5,7,10].…”

Quantification of pendimethalin in soil and garlic samples by microwave-assisted solvent extraction and HPLC method

“…The methods available in the literature for determination of pendimethalin are mostly based on gas chromatography (Engebretson et al 2001;Masahiro et al 2005;Bruzzoniti et al 2006;Shen et al 2007;Valsamaki et al 2007;Arora et al 2008;Zhang et al 2008). The HPLC method was reported based on the ultrasonication extraction procedure for residue determination in tobacco (Liu et al 2004) and for biodegradable metabolite determination in bioslurry (Ramakrishna et al 2008).…”